Adding fiber to reduce net carbs

etompkinsdickey's Avatar


01 Oct, 2011 08:21 AM

Dear Dr. Rosedale,
I would like to know if adding a fiber supplement such as psyllium when eating carbohydrates such as fruit or starchy carbohydrates, will reduce the net carbs being eaten at the meal. For example, if you made a smoothie that had a banana or apple in it but also drank a psyllium drink before the smoothie, would that reduce the carbohydrates of the banana by the fiber in the psyllium drink? Would adding fiber be a way of helping to manage carbs to allow a greater daily allowance or permit one to offset the effect of the carbs when a person finds himself in a situation where he doesn't have a lot of control over the food that is being served?

Thank you.

Showing page 2 out of 2. View the first page

  1. 31 Posted by James Foreman on 16 Jan, 2019 03:24 AM

    James Foreman's Avatar

    OK, I will add my caveat concerning how adding fiber does or does not reduce carbs in a meal. It is generally accepted when figuring the net carbs of a recipe to add all the carbs from all ingredients and subtract all the fiber from all the ingredients to determine the net carbs of the resulting dish. If like some have indicated adding additional fiber does not reduce the net carbs then why do we subtract total fiber of the recipe from today carbs to calculate the net carbs of the dish:

  2. Support Staff 32 Posted by Ken on 16 Jan, 2019 10:57 AM

    Ken's Avatar

    Hi James

    The purpose of subtracting fiber from total carb is to find the total sugar content.

    • non-fiber carbs will eventually covert to sugar, which is not good -- so to find total sugar content, (even if it is said that no sugar is added) you subtract total fiber from total carb to find how much sugar actually there is.
    Total Carbohydrate is the: 
    dietary fiber and non-fiber combined
    Non-fiber will convert to sugar
    Fiber - is a carb, that does not convert to sugar
    Sugar - is a non-fiber carb
    Sugar Alcohol - is sugar
    Starches - converts to sugar


    Ken/   Rosedale Support Team

  3. 33 Posted by Tyler on 02 Mar, 2019 03:48 AM

    Tyler's Avatar

    It wouldn't reduce the overall net carbs of what you eat in the end, no. Using the above example of net carbs being the total amount of carbs from all ingredients in a recipe or dish less the amount of fiber from all ingredients is not correct. You determine the net carbs of a dish by adding all of the net carbs of all of the ingredients together. If you just add psyllium, you're just adding "0" net carbs to what you've already eaten.

  4. 34 Posted by Andy on 25 Mar, 2019 05:12 PM

    Andy's Avatar

    Tyler is correct. I just fact checked him and he’s 100% on point.

  5. 35 Posted by Jonathan on 18 Apr, 2019 03:01 PM

    Jonathan's Avatar

    Adding more fiber will not lower the net carbs. Here is an example, you eat a meal that has 30 carbs and 20 fiber, so that is 10 net carbs. You add 10 more fiber, but what happens if you now have a meal with 40 carbs and 30 fiber, STILL 10 net carbs. Because the finer adds to the total carbs.

  6. 36 Posted by Debbie ameche on 18 May, 2019 05:33 PM

    Debbie ameche's Avatar

    If I add psyllium huskpowder to a baked potato can I reduce any of tha added fiber to get net carbs

  7. 37 Posted by Natasha on 22 Jan, 2020 08:57 AM

    Natasha's Avatar

    Fibre IS A CARB in itself and added to total carbs on labels...
    It is however not digestable by the body and therefor is not converted into sugar and then stored as fat.. we subtract the Fibre from total carbs as the fibre part will just pass through
    So logically adding Fiber will actually not reduce carbs in other foods consumed..... it cannot take hands of simple carbs and take it on the scenic tour through the digestive system and just pass through the body

  8. 38 Posted by diane on 06 Feb, 2020 07:28 PM

    diane 's Avatar

    AHHH - I think I've finally got it! So when the label says 30 carbs, that is INCLUDING the original fiber -- and then they take off JUST THE FIBER AMOUNT to reduce the net carb. So adding fiber, as you say, just adds to the carb content. For a minute, I thought: oh I'll add chia seeds or flax seeds and trick the carb content. I guess you can't cheat reality.

    I never knew fiber counted as carbs! So this was a great lesson - and I'm glad I finally asked Google that question - Can you add fiber to lower the carb count. Now that I'm set straight I can understand the label more clearly.

Reply to this discussion

Internal reply

Formatting help / Preview (switch to plain text) No formatting (switch to Markdown)

Attaching KB article:


Attached Files

You can attach files up to 10MB

If you don't have an account yet, we need to confirm you're human and not a machine trying to post spam.

Keyboard shortcuts


? Show this help
ESC Blurs the current field

Comment Form

r Focus the comment reply box
^ + ↩ Submit the comment

You can use Command ⌘ instead of Control ^ on Mac